Mechanism for rotating the platens of type-writing machines



(No Model'.)

M. G. MERRITT & G. S. HEATH. MECHANISM FOR ROTATING THE PLATENS OF TYPE WRITING MACHINES.

No. 442,129. Patented Dec. 9, 1890.

rrn STATES PATENT OFFICE.

MORTIlilER G. MERRITT AND GEORGE S. HEATH, OF SPRINGFIELD, MASSACHUSETTS.

MECHANlSM FOR ROTATING THE PLATENS OF TYPE-WRITING MACHINES.

SPECIFICATION forming part of Letters Patent No. 442,129, dated December 9, 1890.

Application filed August 4, 1890. Serial No. 360,912. (No model.)

T0 at whom it may concern.-

Be it known. that we, MORTIMER G. MER- Rrr'r and GEORGE S. HEATH, citizens of the United States, residing at Springfield, in the county of llampden-and State of Massachusetts, have in vented new and useful Improvements in Mechanism for Rotating the Platens of Type-\Vriting Machines, of which the following is a specification.

This invention relates to type-writing n1achines, the object being to provide improved means for rotating the platen of said machines; and the invention consists in the peculiar construction and arrangement of the platen-rotatin devices, all as hereinafter full y described, and pointed out in the claims.

In the drawings forming part of this specification, Figure l is a perspective view of one end of the platen of a type-writing machine having applied thereto means for rotating the same embodying our improvements, this figure showing also one end of the platensupporting frame. Fig. 2 is a transverse section of said platen about on line 2, Fig. 4c. Fig. 3 is a transverse section of the platen about on line 3 of Fig. i. Fig. 4 is a longitudinal section of the end of the platen to which the devices for rotating the same are attached.

The withirrdescribed improved platen-rotating devices are adapted to provide for the rotation of the platen within its supportingframe in either direction by grasping the finger-wheel on the extremity of the shaft of the platen, the latter upon the release of said tinger-wheel invariably becoming locked by the action of certain mechanism connected with the platen-shaft, said mechanism acting also through an attempt to rotate the platen by said finger-wheel to unlock. the platen and permit its rotation thereby.

Other mechanism, as fully described below, is provided for rotating the platen in one di rection by operating a horizontally-extending finger-lever for the purpose of spacing the lines of the writing.

In the drawings, 2 is the platen, of the usual hollow cylindrical construction, consisting of the inner metallic cylinder 3,having metallic heads 4-, screwed or suitably attached to each '6 of the platen extends through the latter,

and the ends thereof proj ect beyond the heads thereof and enter the end portions of the platen-frame 8, and the shaft is supported to rotate therein when the platen is turned.

\Vithin the cylinder 3, near one end thereof, is secured in a suitable support 9 a vibratory latch 10, which is pivoted to said support by its rear end at a, Fig. 4, the free end of said latch extending through an opening a in the head 4:, which allows said free end a certain degree of movement toward and from the shaft 6. A spring 12 (shown in partly full and partly dotted lines in said last-named figure) serves to swing the free end of said latch toward the platen-shaft.

To provide means for swinging the free end of the latch 10 from shaft 6, for a purpose below described, a cam-lever 13 is rigidly secured on shaft 6 by a screw or otherwise whose extremity has arecess therein to receive the edge of said latch, having canishaped or curved edges extending each way from its deepest point to the opposite edges of said cam-lever, as clearly shown in Fig. 2. It will be clearly seen that by turningshaft 6 in either direction one of said curved edges of the lever 18 is driven againstthe edge of the latch 10, causing it to swing in a direction from shaft 6, and upon swinging the lever back to the position shown in Fig. 2 spring 12 carries the latch again into the recess in the end of said lever.

A fingerwheel 1% is rigidly secured on the outer end of the shaft- (3, which provides one means for turning said shaft and the platen, as below described.

A ratchet-case 15, of suitable metallic construction and of cup form, is supported indirectly on shaft 6, between the head at of the cylinder 3 and said finger-wheel. Asleeve 10 on shaft 6 extends from the inner end of the hub of said finger-wheel to the outer side of the cylinder-head 4:, as shown in Fig. 4, and said ratchet-case 15 has its central hearing directly on said sleeve, the edge of said cup having a position close to the outer side of said head at and being retained in that position by the frame 8 outside of the cup, a pin or screw ysecuring the cup to the frame. \Vithin the ratchet-cup 15 are located a toothed wheel 17 .and a ratchet-wheel 18, which are secured together as one wheel (with an intermediate separating-disk 19) by one or more rivets 20, (see Fig. 3,) and said wheels 17 and 18 rotate freely on said sleeve 16, and the free end of said'latch 10 has an engagement with said toothed wheel, as shown.

A pawlarm 21 is hung on the sleeve 16 between the ratchet-wheel 17 and the adjoining inner side of the case 15, and has a swinging movement thereon. (see Fig. 3,) secured to case 1 5, has one end bearing on said pawl-arm to swing it downward and another end thereof bearing on a retaining-pawl 23, hung on the inside of case 15 and engaging with the ratchet-wheel 17. The pawl-arm 21 has a pawl 23. hung there on which engages with said ratchet-wheel to turn it, and is held in such engagement bya spring 0.

A pawl-stop 21, having an operating-handle c thereon projecting through the rim of the ratchet-case, is pivotally hung on the inner side of the latter, and the different positions to which said stop may be swung govern the extent of the swinging movement of the pawl-arm 21, and consequently the degree of rotation of the ratchet-wheel and the platen, either to cause the spaces between the lines of writing on paper held on the platen to be wide or narrow. Thus, with the stop 21 in the position shown by full lines in Fig. 3, the arm 21:and its pawl 23' may swing to the greatest extent, as indicated by dotted lines in said last-named figure for a wide-line space; but if said stop be turned to the position indicated by dotted lines in said Fig. 3 the end of the pawl will, when moving the ratchet wheel, engage with the end of the stop and permit a movement only for a narrow-line space. Said pawl-arm is operated by a horizontally-extending line-spacing lever 25, (extending toward the operator,) which is pivotally hung on the frame 8 of the platen, and has its inn-er end K turned at right angles to its main part and extending through a slot h in the end of the ratchet-case to a position under said pawl-arm 21, whereby the latter and the pawl 23 are lifted when the outer end of lever 25 is swung downward.

The operation of the within-described improvements in turning the platen 2 for regularly spacing the type-writing lines on paper held thereby and for rotating the platen independently of said line-spacing lever to facilitate the placing of thepaper in writing position thereon. is as follows, it being understood that with the latch 10 in the position A spring 22,

shown in the drawings the platen is locked against rotation, except by lever 25 or wheel 14. The end of a sheet of paper is entered between a paper-holder D and the platen 2. Then to quickly draw the end of the sheet around the under side of the platen and beneath the paper-guide b to a position to be printed on the operator grasps the fingerwheel 11, and, turning the same and through it shaft 6, swings the cam-lever 13 against the latch 10, (but not away from it,) and forces the latter downward out of engagement with the toothed wheel 17, (which is, as aforesaid, attached to the ratchet-wheel 18.) This disengagement of latch 10 permits the quick rotation of the platen by the wheel 14 independently of the ratchet devices in case 15. Upon the release of the wheel 14 by the operator, the lever 13 and latch 10 resume their normal positions, as shown in Figs. 2 and 4, by the action of the spring 12, which forces the end of latch 10 against one of the curved edges of lever 13.

lVhile an operator is using a typewriting machine having thereon this description of a platen and rotating devices therefor, the linespacing rotary movements of the platen are effected by pressing downward the free end The horizontal arrangement of thelever 25 "writing machine and the shaft thereof, a

latch pivoted within the platen, having a vibratory motion toward and from the axis thereof, a spring to swing one end of said latch toward said axis, a cam-lever on said shaft acting to depress said latch, a toothed wheel mounted on said shaft in proximity to the free end of said latch, with which the lat ter engages, and a finger-wheel fixed on said shaft by which to'rotate it and the platen c0- i-ncidently, substantially as set forth.

* 2. In combination with the platen of a typewriting machine and the shaft thereof, a ratchet-case mounted thereon at one end of the platen and fixed to the frame thereof, a sleeve passing through said frame and case, within which said shaft rotates, a ratchetwheel and a toothed wheel mounted and having coinciding rotary motion on said sleeve within said case, a latch pivoted within the iplaten, normally engaging with said toothed pvheel, a cam-lever on said shaftengaging with said pivoted lever, and aspring holding said latch in engagement with said canvlever and wheel, a pawl-arm within said ease, carrying a pawl in engagement with said ratchetwheel, and an operating-lever hung on the platen-frame, having one end engaging with said pawl-arm, substantially as set forth.

3. In combination, a platen for a type-Writing machine and a shaft on which the same is supported, a paWl-and-ratchet mechanism comprising an operating-lever therefor applied in relation to said shaft, and a latch to act as a clutch between the said ratchet mechanism and said shaft and platen, and a cam on said shaft adapted on the turning of the shaft in either direction to move the latch to disengage the clutch connection between the platen and shaft and the ratchet mechanism, whereby the continued rotation of said shaft may be had independently of the ratchet mechanism, for the purpose set forth.

MQR'IIMER G. MERRITT. GEORGE S. HEATH. Vitnesses:

C. A. BRIGHAM, H. A. CHAPIN. 

